1. Field of the Invention
The present invention relates to a mobile station such as a cellular phone, a communication system, and a telephone communication switching method.
2. Related Background of the Invention
Japanese Patent Application Laid-Open No. 2004-235976 discloses a mobile station such as a cellular phone that can be connected to a wireless LAN access point (hereinafter referred to as a wireless LAN spot) based on a current location. Such a mobile station can be connected to the Internet via a wireless LAN and thus telephone communication using the Internet can be performed. Telephone communication using the Internet is realized by a VoIP function. VoIP is a technology (VoIP: Voice over Internet Protocol) for a mobile station such as a cellular phone connected to a wireless LAN to transmit and receive voice data (voice call) via the Internet.